Orange lake and process of making same.



UNITED srn'rl'is PATENT OFFICE.

RICHARD KIRoHHQFiggr BERLIN, GERMANY, ASSIGNO'R TO ACTIEN GESELLSCHAFTnon uman FABRIKATION, OF BERLIN, GERMAN" ORANGE LAKE AND PROCESSOF'MAKING SAME. 1

Specification of Letters Patent.

7 Patented Jan. 29,,1907.

Application filed July 7, 1905. Serial No. 268,727. (Specimens) To allwhmn it may concern:

Be it known that I, RICHARD KIRCHHOFF, of Berlin, in the Kingdom ofPrussia, German Empire, have invented new and useful Improvements inOrange Lakes and Processes of Makin Same; and I do hereby declare thatthe ollowing' is a full, clear, and exact description thereof, which\W1ll enable others skilled in the art to which it appertains to make'and use the same.

I have discovered that one can obtain valuable oran e-color lakes fromthose mono-ago colors WhlCh are produced by OOHlblllill" 1n the usualmanner the diazo compound '0 an amido-sulfonic acid of the benzene ornaphthalene series with ortho-nitro henol by converting the alkali saltsof sue 1 an azo color into the salts of an alkaline-earth metal, of anearth metal, or of an other suitable metal. For this purpose the alkalisalts of the said dyestuffs are dissolved or suspended in water, and asolution of such a metallic salt as, for instance, a salt of barium,calcium, strontium,'magnesium, or the ox1d or hydroxid of one of thesemetals or amixture of such compoundsis added either in the cold or whileheating. It is preferable to add before or after precipitation asuitable substratum, such as sulfate of calcium, hydroxld of aluminium,or the like. The lakes are then filtered and dried. They osses's a clearorangecolor and are most (hflicultly soluble or nearly insoluble inwater. They also are distinguished by a very great fastness to li ht. Ascoloring-matters which are fit for the purpose of my invention I name,for instance, the following: sulfanilic acid-azoortho-I'litl'o henol,metanilic acid-azo-orthonitropheno chloranilin sulfonicacid-azoorthonitrophenol, 2.6-naphthylamin sulfonicacid-azo-ortho-nitrophenol.,

The following examples may} serve to illustrate my invention, the partsbeing by weight.

Example 1: One hundred parts of a paste containing about twenty percent. of the sodium salt of the dyestuff obtained by combining the diazocompound of sulfanilic acid with ortho-nitrophenol in soda-alkalinesolution are well mixed with two hundred parts of water. 90 centigradeit is added with a solution After heating this mixture to 80 of fortyparts of barium chlorid, whereby the mass 1s to be very well agitated.Some time afterward 800-1 ,000 parts of a freshlyprepared paste ofaluminium h dro 'id containing 2-3 percent. of it are s ow ypoured in,whereafter agitation while heatign is con- .tinued for some furthertime.

T en the mass is filtered, pressed, dried, and very finely ground. T elake thus obtained is nearly insoluble in water and has a great body. Itproduces clear orange tints whichpossess a very great fastness to light.

Example2: Dissolve fiftyparts of aluminium sulfate'in two thousand artsof water, pour in fifteen parts of slaked ime in the form of milk oflime, add two hundred parts of the sodium salt of the dyestufl mentionedin Example 1 dissolved in ten thousand parts of water, and agitate themass very well Add a.solution of-,one hundred and fift parts. of bariumchlorid in fifteen hundred parts of -water and stir the whole for somefurther time. Then filter, press, and dry. The product shows also aclear orange tint and or the rest has the same properties as thatobtained according to Exam le 1.

From the dyestuff used 111 the foregoing examples one can also obtain apure barium lake by precipitating a solution of the sodium salt of thedyestuif only with a barium salt. It results in this way, a lake whichis a little more reddish than that obtained according to Example 1, butwhich possesses likewise a ve clear tint and which is absolutely insolube in water.

According to the method as given in the foregoing examples I may alsoproduce lakes from the other abovc-namedazo colors, as it is obviousthat I am not limited to the above examples nor to the details giventherein.

phenol, which consists in preci itating'the alkali salts of said azocolors wit salts of the alkaline earths.

3. The new orange-color lakes repared by precipitating an alkali salt oft e monoazo colorsdefined in the foregoing specification with salts ofthe alkaline earths 1n the presence of a suitable substratum, said lakesbeing distinguished by a clear orange color, a

. acid azo ortho nitrophenol by means of barium chlorid in the presenceof aluminium ,colored powder having a great body,

hydroxid, said lake being a clear orangeractically insoluble in waterand insoluble iii alcohol, whichpowder when treated with ahot solutionof an alkali is decomposed and converted into the corres onding alkalisalt of the said dyestuff, and om which solution of the alkali salt, byatreatment 'with strong reducing a ents, 2.4-diamidophenol is obtainedbesi es sulfanilic acid.

In witness whereof I have hereunto signed my name, this 22d day of June,1905, in the presence of two subscribing witnesses.

\ v RICHARD =KlRCH-HOFF.

Witnesses:

',HEN'B,Y HASPER,

WOLDEMAR HAUPT.

